1. Field of the Invention
This invention relates to an insect repellent, and in particular to an insect repellent utilizing DEET as the active ingredient.
2. Discussion of the Prior Art
DEET is the generic name for N,N-diethyl-3-methylbenzamide or N,N-diethyl-m-toluamide. The compound has known insect repellent properties (see for example the details provided on pages 1 and 2 of Canadian Patent No. 1,196,278, which issued to E. Charlet et al on Nov. 5, 1985). A variety of another DEET formulations are described in the patent literature.
U.S. Pat. No. 2,403,389, issued to S. I. Gertler on Oct. 1, 1946 discloses DEET-containing insect repellent compositions in the form of a cream, a lotion or a dusting powder.
Canadian Patent No. 887,035, issued to B. T. Gillis on Nov. 30, 1971 discloses a liquid insect repellent which may contain DEET and a solvent selected from a variety of lower alcohols, glycols and hexachloroprene.
Canadian Patent No. 1,106,278, issued to A. Petnakaran on Feb. 4, 1982, discloses a black fly repellent consisting of DEET and vanillin.
Canadian Patent No. 1,196,278, issued to E. Charlet et al on Nov. 5, 1985 describes an insect repellent consisting essentially of DEET in an alcoholic solution and polyethylene glycol.
Canadian Pat. No. 1,196,279, issued to E. Charlet et al on Nov. 5, 1995 relates to an insect repellent containing DEET in an alcoholic solution and castor oil. The composition may also contain water.
Most commercially available, DEET-containing compositions are oily liquids or sprayable solutions. When an oily composition is applied to the skin, the result is a greasy film which dries relatively slowly. When applying a more quick drying spray, it is difficult to produce a uniform coating. In order to coat the entire surface of an area of skin, it is necessary to liberally spray the area often using a large volume of repellent.
An object of the present invention is to provide an insect repellent in semi-solid gel form, which can easily be applied in a uniform manner.
Another object of the invention is to provide DEET-containing insect repellent which dries relatively quickly and does not leave a greasy deposit on the skin.